Knife holder assembly

ABSTRACT

An assembly of holders for the knives of pressure or squeezeacting roller cutting machines for longitudinally cutting webs, particularly of a strong material such as cellulose and cotton wool, includes individual flat knife-holder assemblies having fluid pressure operated movable piston elements which are coupled to the knife through individual mounting elements having forked legs. The forked leg mounting elements are arranged to slide between casing plates. The assembly of knives is such that alternate knife holders or extensions thereof extend between the plates of the next adjacent knife assemblies. In this manner, the pressure casings for the reciprocal piston member which is connected to the forked knife mounting elements are alternately arranged at different mounting levels so that the whole assembly may be compressed within a small space to facilitate the close spacing of the knife elements.

United States Patent Dienes Werke Fur Maschinenteile G.m.b.H. Overath,Germany [73] Assignee [32] Priority Apr. 25, 1968 Germany [31] P 17 61256.5

[54] KNIFE HOLDER ASSEMBLY 5 Claims, 6 Drawing Figs.

2,997,906 8/1961 Burk etal.

Primary ExaminerWilliam S. Lawson Attorney- McGlew and Toren ABSTRACT:An assembly of holders for the knives of pressure or squeeze-actingroller cutting machines for longitudinally cutting webs, particularly ofa strong material such as cellulose and cotton wool, includes individualflat knife-holder assemblies having fluid pressure operated movablepiston elements which are coupled to the knife through individualmounting elements having forked legs. The forked leg mounting elementsare arranged to slide between casing plates. The assembly of knives issuch that alternate knife holders or extensions thereof extend betweenthe plates of the next adjacent knife assemblies. In this manner, thepressure casings for the reciprocal piston member which is connected tothe forked knife mounting elements are alternately arranged atdifferent'mounting levels so that the whole assembly may be compressedwithin a small space to facilitate the close spacing of the knifeelements.

PATENTED FEBZBISYI 3564.962 I sumenra 2ou o0 INVENTOR I 3 PETER HINGE/VMMM 1 PATENTEU FEB23 I97! SHEET 3 [1F 4 INVENTOR 3 Perm WINGEMI'll/Ill/III'IA llliuilnl.

PATENTED FEB23 I97! saw u 0F 4 INVENTOR 8 PETER HINGEN /Wfwo KNIFE uoumnASSEMBLY SUMMARY OF THE INVENTION This invention relates, in general, tothe construction of holders for cutting knives and in particular to anew and useful assembly of holders for pressure-cutting knives of rollercutting machines in which the knives are arranged very closely together.1

The present invention particularly relates to a knife holder assemblywhich includes individual knives which. may be pressed into cooperativecutting positions against a counter roller through the action of apiston movable in a pressure cylinder. Such knives are used principallyfor dividing webs longitudinally, particularly for cuttingstrongmaterial such as cellulose, cotton wool and the like. In the typeof knife holders with which the present invention is concerned, a pistonfor each holder or knife mounting element is-coupled with a forked flatmounting plate or bearing fork. The legs of the forked mounting platefit snugly or flush within guide grooves defined between laterallyspaced casing plates. A pressure casing for the actuating piston which.is connected to the fork plate is constructed as a flat boxlikestructurearranged with its sidewalls extending longitudinally andparallel above the easing plates on each side of the forked'rnountingelement. Knife holders of this type are known, as indicated in GermanPat. No. 1,072,878 and they have the advantage that they are carriessimple in construction and they maybe operated exactly and rapidly. Thisis true because the relative cutting width distances have been set onthe knife beam which carries the holders of the individual knives sothat all of the knives can be operated at the same time and with thesame force against a common pressure roller or counter roller. Pressureforce is set by connecting the individual pressure casings for eachknife through a common pressure source through suitable valve means.

The known construction of the knife assembly as described above permitsa relatively large effective piston cross section with a relativelysmall axial dimension so that a large pressure cutting force can betransmitted through the individual mounting forks to the knives. Becausethe mounting forks for the individual knives are guided with a tight fitbetween the side plates of each assembly, it is capable of transmittinga very large operating knife force.

With the known knife assemblies, narrow strips can be cut away from theweb without interfering with the operation of the pressure transmittingmeans to the individual fork mounting elements. However, for somepurposes, it is desirable to cut still smaller strip widths than hasbeen possible with the known machines. In order-to be able to do so, theknife holders had to be arranged so that they are ofi'set in aperipheral direction and in the axial direction of the pressure roller.This required the fitting of the cutting machine with at least two knifebeams, or the pressure medium actuation had to be replaced byblade-shaped springs which had to be adjusted individually at eachindividual knife holder by means of a tension screw. In addition, inorder to accomplish the adjusting movement, the knife beam had toberotatable or tiltable at the machine.

In accordance with the present invention, a knife assembly is providedwhich is operated by a pressure medium but which is, nevertheless,capable of cutting extremely narrow widths and which permits themounting of the knives very closely together. This is accomplished byarranging alternate pressure housings or casings at one level or spacingand the other pressure housings or casings are offset, i.e., they are ata separate level, for example, a higher level. The pistons of thepressurecasings at the lower level are connected directly to the forkedmembers mounting the individual knives while the pistons of the pressurecasings which are at a higherlevel are connected through extensions tothe forked elements mounting the knives of these holders. The guidewalls which are arranged on each side of the forked knife holders arearranged together in a grooving or stack below the pressure holders atthe lower level. The arrangement is such that the respective extendedand unextended holders may be carried on single knife beams locatedaxially one behind the other or one above the other as the case may be.The construction permits a very small cutting width setting and thesupport walls for the forked knife holders may be arranged flushtogetherin a compact stack which provides a very rigid supportingstructure. Thus, the invention makes it possible to provide an extremelysmall built-in axial dimension of the casing plates to produce the sametechnical force or load in a much smaller width.

With extreme utilization of the possibility suggested by the inventionto decrease the cut width, it may occur that the pressure casing at itsfree rim will be somewhat spread apart by the action of the pressuremedium to cause a lessening of the sealing of the collar at the pressurecasing. This is possible because the pressure casing of the outermostindividual knife assemblies is not supported on the next adjacentmember. In order to overcome this disadvantage, the invention providesmeans for tensioning a screw between the longitudinal walls of thepressure casings above the free rim of the exposed pressure casings. Thetensioning screw is advantageously mounted so that it may be moved withplay in a longitudinal hole at the end of the piston which is on thedriving side. With such an arrangement, the inner walls of the pressurecasing can be arranged parallel and can be adjusted within widetolerance ranges.

Accordingly, it is an object of the invention to provide an improvedknife assembly which includes a plurality of individual knife holderassemblies comprising side plates defining grooves therebetween in whichare slidable individual knife mounting elements. The knife mountingelements are connected to pistons which are movable in fluid pressurehousings or casings to apply the knife pressure to a counter roller.Alternate fluid pressure housings are offset either laterally orvertically from the others and the individual knife mounting members areconnected to the respective pistons in the offset housings of greaterlength by extension plates which extend between the housings of theothers of the individual knife assemblies.

A further object of the invention is to provide a mounting arrangementparticularly for pressure type or compression knives capable of cuttingwebs longitudinally over pressure rollers wherein the housings for themounting elements for the knife are arranged in a flat stack permittingclose lateral spacing of the knives and which advantageously includesmeans for adjusting the seal of a fluid cylinder housing bearing apiston member which is adapted to be connected to the individual knifemounting elements for applying an operating pressure to the knives.

A further object of the invention is to provide an assembly ofhydraulically or pneumatically operable holders for rotating squeezingknives or pressure knives which cooperate with a pressure roller andwhich is simple in design, rugged in construction and economical tomanufacture.

BRIEF DESCRIPTION OF THE DRAWINGS In the Drawings: FIG. 1 is a partialperspective and front elevational view of a knife assembly adjusted tothe smallest cutting width and constructed in accordance with theinvention;

Referring to the drawing, in particular, the invention embodied thereincomprises the construction and arrangement of an overall assemblygenerally designated 60 of individual cutting knife subassembliesgenerally designated 62 and 64.

In accordance with the invention, each of the subassemblies 62 and 64includes a rotary pressure-cut or squeeze-knife 23 having a sharpenededge 24. The knife 23 is mounted in clamping slots 25 at the ends ofknife mounting members or holding plates 26 which have forked legs orends 260 which define the slot 25 for receiving the hub portion of theknives 23. The hubs 10 are supported on roller bearings 16.

Each of the knife mounting members 26 is accommodated within innerguides or grooves 27 defined between laterally spaced casing plates. Themounting plates 26 are arranged with a snug or flush fit within thegrooves 27 so that the hub end faces of the knife 23 are supported in aplay free manner against edging from the inner surfaces of these plates.The mounting plates 26 with the knives 23 are moved in operativepressure engagement against a web (not shown) which is fed over acounter roller or pressure roller 31. The knives are operatively engagedin pressure-cutting contact with a web by a fluid-pressure operatedpiston 2 which is connected to the outer ends of each plate 26. Thepiston 2 is slidable in a pres sure casing or housing 1 and thesqueeze-knife 23 together with the mounting member 26 carried by thepiston 2 can move axially relative to the box-shaped pressure casing I.The displacement of the piston 2 within its housing 1 is accomplished byapplying a fluid pressure force to the piston collar 3 to move the knife23 in a cutting direction. Biasing means such as springs act to move theknives backwardly in a counter or retracting direction. The springs 15are arranged in holes of lining pieces 6 (FIG. 4) in the plates 4 and 5.

Each pressure casing 1 has a larger axial dimension or width than theplates 4 and 5. Each second pressure casing 1 in a row as indicated inFIG. 1 has its end flush with the outer ends of the plates 4 and 5 asindicated in FIGS. 5 and 6, when the knives are in a cutting position.Each alternate plate assembly 62 includes an exterior extension plate28, 7 on respective sides extending between the pressure casing l andthe plates 4 and 5 and ,an extension member extending centrally betweenthe piston 2 and the associated knife mounting plate 26. Securing meanssuch as bolts 8 hold the assemblies together. In this manner, even whenthe smallest cutting width is to be cut, the knife holders may beassembled together with the subassemblies 62 and 64 arranged alternatelyand boxed together to form an overall relatively strong structure asseen in FIG. I. Securing means such as bolts 8 hold the assembly ofplates 4 and 5 and pressure casings 1 together so that it may be mountedas a unit on a holder beam 30.

In order to insure that the pressure casing l is not spread apart at itssealing edge by the action of the pressure medium, the longitudinal rimsor edges of the pressure casing are connected together by an adjustabletension screw 22. The tension screw 22 is arranged with play in alongitudinal slot 29 at a location to permit movement of the connectionof the piston 2 to the extension plate 20 at the location 19 as shown inFIG. 3.

The setting of the holder assembly 60 on the holder beam 30 may beadjusted by a prism mechanism which includes an adjusting screw 12threadably mounted on an extension so that it may bear against a prismor stop 13 which is carried in a fixed end position on a pivot 17 so asto extend angularly below the threaded member l2.

1 claim:

1. An assembly of holders for rotating squeeze-knives which are adaptedto cooperate with a pressure roller for the purpose of longitudinallycutting webs, particularly of a strong material such as cellulose andcotton wool, comprising a plurality of knife holder subassemblies eachincluding side Plates adapted to be arranged closely together with the pates 0 ad acent subassemblies in touching contact for the purpose ofcutting very narrow widths of web material, said side plates of eachsubassembly defining interior knife mounting plate guides, a knifemounting plate mounted for movement in each of said guides, a knifecarried by each of said mounting plates and projecting beyond said sideplates for engagement over a web positioned on the pressure roller, afluid pressure casing for each subassembly, a piston movable in saidfluid pressure casing under the force of fluid actuating pressure andconnected to said knife mounting plate for moving said mounting platewith said knife, said subassemblies being arranged with alternate onesof said pressure casings being in a row which is offset from the row ofthe remaining pressure casings, the connection between the pistons ofsaid offset row of pressure casings to said mounting plate meansextending between the pressure casings of the remaining rows, andsecuring means for securing said side plates and said fluid pressurecasings together in an assembly which may be adjustably positioned inrespect to the pressure roller.

2. An assembly according to claim I, wherein said connection between thepistons of said offset row to said mounting plate includes an extensionmember connected between said plate and said piston.

3. An assembly according to claim 1, wherein said mounting plateincludes a forked end defining a groove, said knife being rotatablymounted in said groove.

4. An assembly according to claim 1, wherein said side plates include aplate on each side of said mounting plate.

5. An assembly of holders for rotating squeeze-knives which are adaptedto cooperate with a pressure roller for the purpose of longitudinallycutting webs, particularly of a strong material such as cellulose andcotton wool, comprising a plurality of knife-holder subassemblies eachincluding side plates adapted to be arranged closely together with theplates of adjacent subassemblies in touching contact for the purpose ofcutting very narrow widths of web material, said side plates of eachsubassembly defining interior knife mounting plate guides, a knifemounting plate mounted for movement in each of said guides, a knifecarried by each of said mounting plates and projecting beyond said sideplates for engagement over a web positioned on the pressure roller, afluid pressure casing for each subassembly, a piston movable in saidfluid pressure casing under the force of fluid actuating pressure andconnected to said knife mounting plate for moving said mounting platewith said knife, said subassemblies being arranged with alternate onesof said pressure casings being in a row which is offset from the row ofthe remaining pressure casings, the connection between the pistons ofsaid offset row of pressure casings to said mounting plate meansextending between the pressure casings of the remaining row, saidpressure casing including sidewalls, and at least one tensioning screwextending between said sidewalls for holding said sidewalls together,said connection from said piston to said knife mounting plates includinga longitudinally extending slot accommodating said tensioning screw.

1. An assembly of holders for rotating squeeze-knives which are adaptedto cooperate with a pressure roller for the purpose of longitudinallycutting webs, particularly of a strong material such as cellulose andcotton wool, comprising a plurality of knife holder subassemblies eachincluding side plates adapted to be arranged closely together with theplates of adjacent subassemblies in touching contact for the purpose ofcutting very narrow widths of web material, said side plates of eachsubassembly defining interior knife mounting plate guides, a knifemounting plate mounted for movement in each of said guides, a knifecarried by each of said mounting plates and projecting beyond said sideplates for engagement over a web positioned on the pressure roller, afluid pressure casing for each subassembly, a piston movable in saidfluid pressure casing under the force of fluid actuating pressure andconnected to said knife mounting plate for moving said mounting platewith said knife, said subassemblies being arranged with alternate onesof said pressure casings being in a row which is offset from the row ofthe remaining pressure casings, the connection between the pistons ofsaid offset row of pressure casings to said mounting plate meansextending between the pressure casings of the remaining rows, andsecuring means for securing said side plates and said fluid pressurecasings together in an assembly which may be adjustably positioned inrespect to the pressure roller.
 2. An assembly according to claim 1,wherein said connection between the pistons of said offset row to saidmounting plate includes an extension member connected between said plateand said piston.
 3. An assembly according to claim 1, wherein saidmounting plate includes a forked end defining a groove, said knife beingrotatably mounted in said groove.
 4. An assembly according to claim 1,wherein said side plates include a plate on each side of said mountingplate.
 5. An assembly of holders for rotating squeeze-knives which areadapted to cooperate with a pressure roller for the purpose oflongitudinally cutting webs, particularly of a strong material such ascellulose and cotton wool, comprising a plurality of knife-holdersubassemblies each including side plates adapted to be arranged closelytogether with the plates of adjacent subassemblies in touching contactfor the purpose of cutting very narrow widths of web material, said sideplates of each subassembly defining interior knife mounting plateguides, a knife mounting plate mounted for movement in each of saidguides, a knife carried by each of said mounting plates and projectingbeyond said side plates for engagement over a web positioned on thepressure roller, a fluid pressure casing for each subassembly, a pistonmovable in said fluid pressure casing Under the force of fluid actuatingpressure and connected to said knife mounting plate for moving saidmounting plate with said knife, said subassemblies being arranged withalternate ones of said pressure casings being in a row which is offsetfrom the row of the remaining pressure casings, the connection betweenthe pistons of said offset row of pressure casings to said mountingplate means extending between the pressure casings of the remaining row,said pressure casing including sidewalls, and at least one tensioningscrew extending between said sidewalls for holding said sidewallstogether, said connection from said piston to said knife mounting platesincluding a longitudinally extending slot accommodating said tensioningscrew.